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CW2AEX Class

This class is used by the string conversion macros CT2AEX, CW2TEX, CW2CTEX, and CT2CAEX, and the typedef CW2A.

Important

This class and its members cannot be used in applications that execute in the Windows Runtime.

template< 
int t_nBufferLength= 128 
> 
class CW2AEX

Parameters

  • t_nBufferLength
    The size of the buffer used in the translation process. The default length is 128 bytes.

Members

Public Constructors

Name

Description

CW2AEX::CW2AEX

The constructor.

CW2AEX::~CW2AEX

The destructor.

Public Operators

Name

Description

CW2AEX::operator LPSTR

Conversion operator.

Public Data Members

Name

Description

CW2AEX::m_psz

The data member that stores the source string.

CW2AEX::m_szBuffer

The static buffer, used to store the converted string.

Remarks

Unless extra functionality is required, use CT2AEX, CW2TEX, CW2CTEX, CT2CAEX, or CW2A in your code.

This class contains a fixed-size static buffer which is used to store the result of the conversion. If the result is too large to fit into the static buffer, the class allocates memory using malloc, freeing the memory when the object goes out of scope. This ensures that, unlike text conversion macros available in previous versions of ATL, this class is safe to use in loops and that it won't overflow the stack.

If the class tries to allocate memory on the heap and fails, it will call AtlThrow with an argument of E_OUTOFMEMORY.

By default, the ATL conversion classes and macros use the current thread's ANSI code page for the conversion. If you want to override that behavior for a specific conversion, specify the code page as the second parameter to the constructor for the class.

The following macros are based on this class:

  • CT2AEX

  • CW2TEX

  • CW2CTEX

  • CT2CAEX

The following typedef is based on this class:

  • CW2A

For a discussion of these text conversion macros, see ATL and MFC String Conversion Macros.

Example

See ATL and MFC String Conversion Macros for an example of using these string conversion macros.

Requirements

Header: atlconv.h

See Also

Reference

CA2AEX Class

CA2CAEX Class

CA2WEX Class

CW2CWEX Class

CW2WEX Class

Other Resources

ATL Class Overview